The Prevalence of Uncorrected Refractive Errors in Adolescents Incarcerated in a Youth Detention Center

The purpose of this study was to determine the number of residents requiring corrective lenses in a youth detention center for juveniles from 12 to 18 years old over a 2-year period. A greater number of adolescents incarcerated for criminal activity in a detention center had uncorrected refractive errors (34.87 %) as compared to a comparable population in the public school system (22 %). The prevalence of significant refractive errors among incarcerated adolescents in this study is significantly higher than has been reported previously. The current study found a refractive error rate of almost 35 %. This difference can be explained by a number of factors in their social environments and identifies an area for potential intervention to reduce antisocial behavior in this population.     

Measurement of non-randomness in spatial distributions

Summary The measurement of departure from randomness in spatial distributions has widespread application in ecological work. Several “indices of non-randomness” are compared with regard to their dependence on sample number, sample size and density. Criteria for the best choice of index for specific situations are discussed. A new coefficientC _x is proposed for use with positively contagious distributions and tests of significance are given. WhenC _x and another index (S ²/m−1) are used for positive and negative contagion respectively, values ranging from −1 through 0 (random) to +1 are obtained, regardless of sample number, sample size or density.     

End-to-end process management: implications for theory and practice

The term ‘end-to-end’ process management is now commonplace in the language and practice of operations. Managers are encouraged to migrate from functional process management to end-to-end process management to realise a range of performance improvements. However, these improvements are often elusive; the specific challenges associated with such a migration are under-researched. This paper uses a cross-sector study to identify the challenges of end-to-end process management and to generate practical managerial guidance. Three areas are identified that demand particular managerial attention: the need to move beyond process mapping, the role of IT in process management and maintaining the process infrastructure as a strategic asset. More significantly, the findings highlight the need for greater conceptual clarity regarding the end-to-end concept itself. The existing literature suggests that scope is the primary differentiator of the end-to-end process – the requirement to manage an extended boundary from customer order through to customer fulfilment. However, this research suggests that the end-to-end concept is more complex, comprising of three core constructs with seven dimensions: scope (boundary conditions, sequence/flow and controls); scale (resources and input/output transformation) and complexity (interrelationships and orientation). End-to-end process management involves much more than an extended boundary. It requires a systemic perspective and clarity regarding controls and transforming resources.     

Diesel Engine Exhaust and Lung Cancer Mortality: Time‐Related Factors in Exposure and Risk

To develop a quantitative exposure‐response relationship between concentrations and durations of inhaled diesel engine exhaust (DEE) and increases in lung cancer risks, we examined the role of temporal factors in modifying the estimated effects of exposure to DEE on lung cancer mortality and characterized risk by mine type in the Diesel Exhaust in Miners Study (DEMS) cohort, which followed 12,315 workers through December 1997. We analyzed the data using parametric functions based on concepts of multistage carcinogenesis to directly estimate the hazard functions associated with estimated exposure to a surrogate marker of DEE, respirable elemental carbon (REC). The REC‐associated risk of lung cancer mortality in DEMS is driven by increased risk in only one of four mine types (limestone), with statistically significant heterogeneity by mine type and no significant exposure‐response relationship after removal of the limestone mine workers. Temporal factors, such as duration of exposure, play an important role in determining the risk of lung cancer mortality following exposure to REC, and the relative risk declines after exposure to REC stops. There is evidence of effect modification of risk by attained age. The modifying impact of temporal factors and effect modification by age should be addressed in any quantitative risk assessment (QRA) of DEE. Until there is a better understanding of why the risk appears to be confined to a single mine type, data from DEMS cannot reliably be used for QRA.     

Reanalysis of the DEMS Nested Case‐Control Study of Lung Cancer and Diesel Exhaust: Suitability for Quantitative Risk Assessment

The International Agency for Research on Cancer (IARC) in 2012 upgraded its hazard characterization of diesel engine exhaust (DEE) to “carcinogenic to humans.” The Diesel Exhaust in Miners Study (DEMS) cohort and nested case‐control studies of lung cancer mortality in eight U.S. nonmetal mines were influential in IARC's determination. We conducted a reanalysis of the DEMS case‐control data to evaluate its suitability for quantitative risk assessment (QRA). Our reanalysis used conditional logistic regression and adjusted for cigarette smoking in a manner similar to the original DEMS analysis. However, we included additional estimates of DEE exposure and adjustment for radon exposure. In addition to applying three DEE exposure estimates developed by DEMS, we applied six alternative estimates. Without adjusting for radon, our results were similar to those in the original DEMS analysis: all but one of the nine DEE exposure estimates showed evidence of an association between DEE exposure and lung cancer mortality, with trend slopes differing only by about a factor of two. When exposure to radon was adjusted, the evidence for a DEE effect was greatly diminished, but was still present in some analyses that utilized the three original DEMS DEE exposure estimates. A DEE effect was not observed when the six alternative DEE exposure estimates were utilized and radon was adjusted. No consistent evidence of a DEE effect was found among miners who worked only underground. This article highlights some issues that should be addressed in any use of the DEMS data in developing a QRA for DEE.     

The Pursuit of Productivity

This study names a pantheon of entrepreneurs and managers who have introduced a range of far‐reaching productivity innovations throughout modern history. The thread tying together all of the innovations, in whatever sector of the economy one examines, is the theory of swift, even flow. The study argues why swift, even flow explains the power and long‐lasting nature of these innovations and why other factors thought by some to affect productivity fall short.     

Determinants of Interoutsourcing: An Analytical Approach

Interoutsourcing is a round‐way process in which the vendor is its customer's customer and the customer is its vendor's vendor. While interoutsourcing is emerging as a prominent outsourcing strategy in many industries, there are no rigorous analytical studies focusing on this mechanism. In this article, we analytically demonstrate the efficacy of interoutsourcing by comparing it with normal outsourcing. Our results show that, compared with normal outsourcing, interoutsourcing acts as a self‐enforcer of vendor firms' behaviors toward increasing outsourcing service value. However, in situations where there is a mismatch of outsourcing activities, a high degree of incentive that is based on outsourcing service value, and a high cost of capital, interoutsourcing is not preferred to normal outsourcing. We discuss these results in detail and provide managerial implications for firms involved in interoutsourcing decisions.     

The foundations of econometrics-are there any

The conclusions of alogically consistent economic theory which strictly adheres to Aristotle's axioms of logic are factually true if its sufficient conditions are all factually true. Alternatively, if a conclusion of such a theory is false, then at- least one of its assumptions is false. Unfortunately, the factual truth of sufficient conditions cannot be established because the problem of induction i s impossible t o solve. It is algo true that the falsity of a conclusion cannot be established in the presence of uncertainty. While the philosophy of instrumentalism applied to sufficient and logically consistent explanations may provide useful solutions to immediate practical problems, the principles of simplicity, parsimony and profligacy--all of them requiring conditional deductive arguments--are useless as criteria for model choice.     

The Use of Lay Assessors

This paper reports on some findings from a research study conductedby the authors for the Commission for Social Care Inspection.It examines the reasons for the involvement of lay assessorsand perceptions of the effectiveness of lay assessors in specificregulatory functions.     

Medical Negligence and Resource Allocation in the NHS

The recent growth in medical malpractice claims and in awards for damages has created concern both amongst doctors and health administrators. Steps which have been taken by the Review Body on Doctors’and Dentists’Remuneration and policy now advocated by the BMA suggest a movement away from the current system of negligence and towards a stricter no-fault system of liability. Under the current system, medical negligence occurs when doctors have not met the standards of treatment expected by reference to current professional standards. Under a no-fault system patients would be entitled to compensation for losses which arise from treatment, irrespective of whether negligence had occurred; although the implication is that the amounts of compensation would necessarily be limited. While there are reasons to believe that financial difficulties for doctors and pressures on NHS budgets may be ameliorated by a no-fault system, there are other criteria against which the current system of negligence should be judged. This article attempts to provide a framework within which a negligence system may be assessed. In particular, attention is drawn to the educative role of a negligence system and to the provision of information which may improve decisions on resource allocation. A critique of the current system of medical negligence in the UK suggests that a package of reforms to improve the system would be better than further movements towards non-market solutions.